EP2977665A2 - Flange connection assembly for a coolant pipe and flange - Google Patents

Abstract

The invention relates to a flange connection arrangement 1 for a refrigerant line, comprising a first flange 2 and a second flange 3, wherein the first flange 2 comprises a first material, wherein the second flange 3 comprises a second material, wherein the first material and the second material from each other are different, and wherein the first material and the second material differ in particular in their electrochemical potential in such a way that they form a local electrochemical element together.

Description

The invention relates to a flange connection arrangement for a refrigerant line according to claim 1 and a flange for a connection point in a refrigerant line according to claim 8.

Pipe systems of vehicle air conditioning systems, especially those which are operated with R744 or a comparable refrigerant, need for each connection a preferably releasable coupling system, which consists of two support parts. In general, the coupling system is designed as a flange connection arrangement with a first and a second flange, in particular with a pin having a male flange and a recessed annular groove having a female flange. The flanges are preferably screwed interlocking or clamped together in a different way. In order to meet the high tightness requirements, a sealing element in the form of a metallic disc or a cutting ring is also used.

From the German patent application DE 102 61 887 A1 shows a pipe coupling for the detachable coupling of pipe sections of a high-pressure piping system, which are each firmly connected to a coupling block, one of which has a coupling pin and the other for this a pin receiving, wherein the coupling blocks are held together by a clamping screw of a Seitenflanschverbindung. The coupling blocks are preferably made of an aluminum alloy.

From the German patent application DE 103 26 958 A1 is a connection device for connecting two ducts with a first coupling half, which is penetrated by one of the ducts, with a second coupling half, which is penetrated by the other duct, with a sealing arrangement between the ducts, with a clamping device which is laterally spaced from the Sealing arrangement is arranged, and with at least one serving to support one of the coupling halves and arranged on the other coupling half wedge surface known, wherein the wedge surface of the clamping device is arranged opposite to the sealing arrangement. Sloping surface areas in this case act together in the manner of a wedge gear, which shifts the force applied by a clamping bolt in the central axis of the fluid channel or at least in a region which leads approximately perpendicularly through the seal assembly surrounding the fluid channel. Also in this case, the two coupling halves are preferably formed from an aluminum alloy. In these as in other Flanschverbindungsanordnungen different embodiments, the problem is that when operating a vehicle air conditioning with the refrigerant R744 due to the prevailing temperatures and the high permeability of the refrigerant CO _2, the flexible lines at least on the high pressure / hot gas side no longer as elastomer hose, but as Metal hose must be performed. This metal hose must be made of steel, in particular of austenitic stainless steel, due to the durability and flexibility requirements. The integration of this material in the cost and weight reasons otherwise executed in aluminum or an aluminum alloy piping system proves to be so difficult, since both strength and corrosion aspects a cohesive connection of aluminum or its alloys with austenitic stainless steel meets significantly lower requirements than single-material cohesive connections.

As is apparent from the above examples, the flanges of a flange joint assembly are typically made uniformly from a common material, particularly an aluminum alloy. As a result, they are lightweight and can be produced cost-effectively, for example from extruded profiles. The transition point between aluminum or an aluminum alloy and an austenitic, stainless steel alloy is structurally placed in the tube geometry itself, for example by pipe sections or metal hoses, for example, by a Reibverschweißung or compression - with or without inserted seal - are interconnected. In this case, a direct contact of the various materials is inevitable, and because of their very different electrochemical potentials, a local element is formed, which favors the electrochemical contact corrosion in the presence of an electrolyte. Due to the positioning of such a transition point in an engine compartment of a motor vehicle such a compound is sprayed water and other external influences such as salt, oil, impurities, particles, and / or other corresponding influences exposed due to the relatively thin design of the less noble partner, in this Trap particular of the pressure-bearing tube made of aluminum or an aluminum alloy, leading to premature failure of the refrigerant circuit by leaking.

The invention has for its object to provide a Flanschverbindungsanordnung and a flange for a junction in a refrigerant pipe, said problems do not occur.

The object is achieved by providing the subject matters of the independent claims. Advantageous embodiments emerge from the dependent claims.

The object is achieved in particular by providing a flange connection arrangement for a refrigerant line, which has a first flange and a second flange, wherein the first flange has a first material, and wherein the second flange has a second material. The first material and the second material are different from one another, wherein the first and the second material differ in particular in their electrochemical potentials in such a way that they form a local electrochemical element with one another. In this way, the junction of two different materials of the refrigerant pipe is placed in the flange connection arrangement, wherein each of the two flanges is preferably materially connected to an associated pipe or tube member having that material or consists of that material, which is also the corresponding flange having. This has the advantage that the connection point no longer has to be arranged in the region of the tube geometry itself, wherein it can be placed outside of a pressure-bearing region, preferably in an area where significantly greater material thicknesses are present than in the tube geometry itself. This greater material thickness can now as "sacrificial material" for extending the life of the refrigerant circuit In this case too, direct contact between the two materials is unavoidable from a constructional point of view. There are considerable advantages if the various materials used in the refrigerant circuit do not collide in the region of the pipelines, but rather in the region of the flange connection arrangement where they meet in the form of flanges having different materials.

An embodiment of the flange connection arrangement is preferred, which is characterized in that the first flange comprises steel, in particular stainless steel, preferably stainless steel, particularly preferably ferritic, martensitic or austenitic steel, in particular austenitic stainless steel, the first flange preferably made of steel, in particular stainless steel, preferably stainless steel, particularly preferably ferritic, martensitic or austenitic, in particular austenitic stainless steel. Such a ausgestalteter first flange can readily and in particular without the risk of formation of a local element at the point of contact are materially connected to a metal hose or metal tube, which / in turn made of steel, especially of ferritic, martensitic or austenitic, especially austenitic stainless steel is.

Alternatively or additionally, the second flange preferably has a light metal or a light metal alloy, in particular aluminum or an aluminum alloy. The second flange preferably consists of a light metal or a light metal alloy, in particular aluminum or an aluminum alloy. It is also possible that the second flange has magnesium or a magnesium alloy or consists of magnesium or a magnesium alloy. Other light metals or light metal alloys are of course possible. Such a trained second flange can readily and in particular without the risk of forming a local element with a metal tube or a metal tube are materially connected, which / which in turn is made of a light metal or a light metal alloy, in particular of the same material as the flange itself ,

An embodiment of the flange connection arrangement is also preferred, which is characterized in that the first flange and the second flange abut one another in a contact region arranged outside a sealing region, wherein the contact region has a surface area minimized in terms of load. In this way, the contact between the two materials of the flanges is limited to a load selected minimum, so that in particular the area in which contact corrosion can occur is minimized.

The weight-minimized surface area is preferably from at least 10 mm ² to at most 150 mm ² , preferably from at least 25 mm ² to at most 100 mm ² , preferably from at least 35 mm ² to at most 75 mm ² , particularly preferably 50 mm ² . According to the invention it has been recognized that even such small contact surfaces between the flanges allow a load-compatible flange connection, at the same time the problems of a local element forming and a corrosion at the contact point be significantly reduced by the minimized area.

Particularly preferably, the first flange has a correspondingly minimized contact surface with a corresponding surface area. This brings with it special advantages if the first flange comprises steel or consists of steel. Since this is the more noble material of the flange joint assembly which does not corrode, it is not necessary to provide corresponding "sacrificial material" to the first flange. Therefore, the contact surface can be minimized at this flange in a particularly favorable manner.

An embodiment of the flange connection arrangement is preferred, which is characterized in that the second flange has a first bore for passage of refrigerant, which is aligned with a first bore of the first flange for the passage of refrigerant. Thus, the two flanges each have first holes which are aligned with each other and through which refrigerant can be passed.

It is preferably provided that the second flange has a second bore, in particular a through-bore or a threaded bore, for receiving a fastening means, preferably a screw. This second bore is aligned with a second bore of the first flange, in particular a threaded bore or a through hole, for receiving the fastening means, preferably the screw. Accordingly, the second bores serve in particular for fastening the two flanges to one another. It is possible that one of the two second holes is designed as a threaded bore, wherein the other of the second holes is formed as a through hole. It is then possible to guide a screw through the through hole and screw it into the threaded hole. As a result, the two flanges can be securely and stably fixed to each other.

An embodiment of the flange connection arrangement is also preferred, which is characterized in that the first flange has a projection surrounding the first bore. The projection is preferably designed as a pin, so that the first flange is designed in particular as a male flange. In this case, the second flange preferably has a recess embracing its first bore, more preferably an annular groove. In this respect, the second flange is formed in this case as a female flange. The projection of the first flange preferably engages in the recess of the second flange.

Alternatively, it is possible for the first flange to have a recess which surrounds the first bore, in particular an annular groove, the second flange having a projection embracing its first bore. In this case, the projection of the second flange engages in the recess of the first flange. In this case, then the first flange is designed as a female flange and the second flange as a male flange. The projection of the second flange is preferably formed as a pin.

With the connection of a male flange to a female flange, in particular, a flange connection arrangement can be realized, as is the case with the geometric configuration for example, from the German patent application DE 102 61 887 A1 is known. Such a flange connection arrangement is characterized by a high density and at the same time a high stability of the connection.

An embodiment of the flange connection arrangement is also preferred, which is characterized in that a sealing element is arranged in the recess, which surrounds the first bore of the first or of the second flange. In particular, the flange connection arrangement in a sealing region preferably has a sealing arrangement which consists of at least one annular groove receiving a sealing element and a sealing surface of the male and female flange on which a sealing element is placed. The sealing element is preferably formed as a sealing ring - in particular in the form of a flat gasket, preferably in the form of a - seen in cross-section - rectangular sealing ring formed, which preferably consists of a soft metal. The projection of one flange and the recess, in particular the annular groove of the other flange each have radial sealing surfaces, wherein such a sealing surface is preferably provided in particular on an end face of the projection. At least one of the sealing surfaces preferably has a circumferential profiling, which can press into the sealing ring. Particularly preferably, both sealing surfaces on such a circumferential profiling. The profiling may have annular grooves which are arranged concentrically to each other. It is also possible for the profiling to have peripheral ribs which are circular in cross section and have a triangular shape. A sealing element of soft metal has the advantage that it is impermeable to CO ₂ . A sufficient tightness the connection can be ensured in particular by pressing the profiling into the material of the sealing element.

An embodiment of the flange connection arrangement is also preferred, which is characterized in that an electrically insulating intermediate layer is arranged between the first flange and the second flange in the contact region. As a result, an actual formation of a local element can be effectively prevented, or the risk of resulting contact corrosion can be minimized. In order to realize the electrically insulating intermediate layer, preferably at least one of the flanges has an electrically insulating layer on a contact surface to the other flange. It is preferably provided that the electrically insulating layer is formed as an electrically insulating coating. But it is also possible that the electrically insulating intermediate layer is arranged as an additional component between the flanges, wherein the additional component may for example consist of plastic material.

In a preferred embodiment of the flange connection arrangement, a tensioning device is provided, which is arranged at a distance from the sealing arrangement-in particular between the sealing area and the contact area-between the two flanges. By means of the clamping device, a pressure-tight connection between the flanges, in particular between the male flange and the female flange produced. It is possible that the clamping device has a clamping screw, but there are also other suitable clamping devices conceivable.

The object underlying the invention is in particular also achieved by providing a flange for a connection point in a refrigerant line, in particular for a flange connection arrangement according to one of the aforementioned embodiments, which has a first bore for the passage of a refrigerant. On the flange is - separately from a sealing area - formed in a contact area, a contact surface for abutment with a further flange of a Flanschverbindungsanordnung, wherein the contact surface has a minimally burdened surface content. As a result, the advantages already mentioned in connection with the flange connection arrangement are realized.

In a preferred embodiment of the flange, the surface area of the contact surface is from at least 10 mm ² to at most 150 mm ² , preferably from at least 25 mm ² to at most 100 mm ² , preferably from at least 35 mm ² to at most 75 mm ² , particularly preferably 50 mm ² . This results in a total of small contact surface between the two flanges, wherein at the same time sufficient strength during operation and assembly a particularly favorable behavior is achieved with respect to contact corrosion.

An embodiment of the flange is also preferred, which is characterized in that it has a lightweight construction, in particular outside a sealing region. This may in particular be a bionic structure, ie a bionically optimized structure, ie a structure which is optimized on the basis of bionic considerations and / or criteria. Preferably, the flange has a profiled structure or a truss structure on. In such structures material is advantageously taken away in places where it does not necessarily have to be present, so ultimately a flange stabilizing and supporting lightweight structure is formed, which has significantly less weight than a flange made of solid material, while being highly resilient. In particular, a minimum structure found by bionic considerations preferably has just as much material as is required for pressure stability during assembly and operation of the flange in a flange connection arrangement. This not only allows a significant weight savings over a conventionally designed flange, but also minimizes the space required for this.

In this context, an embodiment of the flange is particularly preferred, which is characterized in that the material of the flange is concentrated in higher loaded areas or in areas of load paths, ie in areas where, especially during assembly or operation of a Flanschverbindungsanordnung, which the flange has increased loads or load paths are to be expected. Preferably, material is recessed in at least one less loaded area. Particularly preferably, it is provided that the flange has no material in at least one less loaded area. As a result, significant weight savings can be achieved without sacrificing stability and strength. Alternatively or additionally, it is provided that the flange has at least one strut extending in a loading direction. In particular, a required stiffness of the flange is achieved by constructive bracing in the loading directions.

An embodiment of the flange with a lightweight structure according to one of the embodiments described above is particularly advantageous in connection with the minimized load content minimized surface area of the contact surface. Since in this case no full-surface contact of the flanges is realized together, a deflection of the minimized with respect to its contact surface flange in an exempt area - especially between a sealing area and the contact area and especially in the area of a clamping device - to be feared. Such bending can be avoided by the flange has a suitable lightweight structure with load distributed material and in particular extending in the direction of loading struts. He wins this increased rigidity, so that despite the burden-minimized contact surface no deflection must be feared.

In this context, in particular an embodiment of the flange is preferred, which is characterized in that it has at least two substantially parallel, preferably parallel plates. In a preferred embodiment, the flange has exactly two substantially parallel, preferably parallel plates. The plates are spaced apart by web-like structural elements, in particular by webs, and connected to each other. It is thus created a lightweight structure in which the rigidity is effected in particular by the webs which connect the two plates together. The first bore of the flange preferably extends perpendicular to the plates. In particular, the first bore preferably extends through the plates and between the plates through a substantially cylindrical, preferably cylindrical first Passage structure. The two plates are also spaced by the passage structure and interconnected. Preferably, the flange is recessed outside the passage structure and the web-like structural elements, thus has no material outside of their areas. This makes it at the same time light and stiff. The web-like structural elements prevent a bending of the flange particularly effective.

It is also preferred an embodiment of the flange, which is characterized in that it has a second bore, in particular a through hole or a threaded bore, for receiving a fastening means, preferably a screw. By means of the fastening means, two flanges of a flange connection arrangement can be connected to one another or fastened to one another. The second bore preferably extends - in particular perpendicular to the plates - through the plates of the flange and between the plates through a substantially cylindrical, preferably cylindrical second passage structure. If the second bore is formed as a threaded bore, the thread is preferably also formed in the second passage structure. But it is also possible that a threaded sleeve is introduced into the second passage structure and held therein. An appropriate attachment using a screw is particularly easy and efficient to produce, while it is also very reliable.

It is also preferred an embodiment of the flange, which is characterized in that the second bore is arranged centrally on the flange, wherein the contact region is arranged in an outer region of the flange. A surrounding the second hole, inner area of the flange is free of a contact surface. In this area so material is optional, so that the flange touches the other flange of the flange connection arrangement only on the one hand in a sealing area and on the other hand in the outer contact area. In this case, the contact region is preferably symmetrical, particularly preferably viewed from the second bore symmetrical to the first bore or to a projection or a recess which surrounds the first bore, in particular so arranged symmetrically to the sealing region in the outer region of the flange. In this way, in the region of the second bore, a clamping force can be applied centrally and preferably symmetrically between the sealing region on the one hand and the contact region on the other hand, so that a very tight connection without tilting is possible.

In a preferred embodiment, it is provided that the contact region has two partial contact surfaces, which are preferably spaced apart from each other by at least one recess, so that the two partial contact surfaces together with the sealing region form a support triangle. The second bore and thus in the assembled state, a clamping screw is preferably provided in the center of gravity of this triangle arrangement, whereby a particularly dense and stable connection is realized.

The flanges touch only in the sealing area - where they are, however, spaced from each other by the sealing element - and in the contact area, which is minimized load, so that overall the risk of contact corrosion is significantly reduced.

An embodiment of the flange is also preferred, which is characterized in that the contact surface is provided with an electrically insulating layer. Particularly preferably, the contact surface is provided with an electrically insulating coating. This further minimizes the risk of contact corrosion or the formation of a local element.

If the flange has a light metal or a light metal alloy, it can readily be produced in a conventional production method, for example by machining or by extrusion or in a combination of these production methods.

However, an embodiment of the flange connection arrangement is preferred, which is characterized in that the first flange of the flange connection arrangement is formed as a flange according to one of the embodiments described above.

It is particularly preferably provided that the flange steel, in particular stainless steel, in particular stainless steel, preferably ferritic, martensitic or austenitic, in particular austenitic stainless steel, or consists of one of said materials. In this case, there are special synergy effects, because the flange, which consists of the nobler material, is provided with a lightweight structure, wherein material is recessed, which is readily possible, since no "sacrificial material" must be provided here. In addition, the materials mentioned are the heavier material of the flange connection arrangement, so that the design with a lightweight structure has corresponding weight advantages and a significant weight saving for the Flanschverbindungsanordnung brings with it.

However, it also turns out that a flange made of steel in a conventional production method is significantly harder to produce than a light metal material due to the lower cutting speed. In addition, due to the higher specific gravity of the steel material in such an embodiment, a corresponding weight increase of the air conditioning or the entire air conditioning cycle seems inevitable. The lightweight structure of the stainless steel flange is difficult to produce at an acceptable cost due to the complicated geometry in conventional machining technology.

An embodiment of the flange is preferred, which is characterized in that the flange is made in a process selected from a group consisting of a generative manufacturing process, an additive manufacturing process, a metal powder injection molding process, a precision casting process, a forging process, and a machining process. In particular, in a generative manufacturing process, an additive manufacturing process, a metal powder injection molding process, a forging process and investment casting process realize the benefits of high imaging accuracy and surface quality, in particular in a metal powder injection molding process no or minimal reworking of the contours and surfaces must be provided. Therefore, this represents a particularly preferred production method for the flange. In particular, steel flanges with a suitable lightweight structure can be easily produced by means of the aforementioned methods.

On the other hand, a flange comprising a light metal or a light metal alloy may preferably be produced by a machining process, or alternatively by extrusion, or by a combination of these processes. Even a production by forging is possible.

The description of the flange on the one hand and the flange connection arrangement on the other hand are complementary to each other insofar as features which have been explained explicitly or implicitly for the first flange in connection with the flange connection arrangement, preferably individually or combined with one another, are features of a preferred embodiment of the flange. Features that have been explicitly or implicitly described in connection with the flange are preferably individually or combined features of the first flange of an embodiment of the Flanschverbindungsanordnung. In particular, the first flange of the flange connection arrangement preferably comprises steel, wherein it also has a lightweight structure. At the same time, the second flange preferably has aluminum or an aluminum alloy, wherein it preferably has no lightweight structure.

Figur 1

eine schematische Längsschnittansicht eines Ausführungsbeispiels einer Flanschverbindungsanordnung;

Figur 2a)

eine Detailansicht des Ausführungsbeispiels gemäß Figur 1;

Figur 2b)

eine Detailansicht analog zu Figur 2a eines weiteren Ausführungsbeispiels der Flanschverbindungsanordnung;

Figur 3a)

eine erste Ansicht eines Ausführungsbeispiels eines Flanschs, und

Figur 3b)

eine zweite Ansicht des Ausführungsbeispiels des Flanschs gemäß Figur 3a).

The invention will be explained in more detail below with reference to the drawing. Showing:

FIG. 1

a schematic longitudinal sectional view of an embodiment of a Flanschverbindungsanungsanordnung;

FIG. 2a)

a detailed view of the embodiment according to FIG. 1 ;

FIG. 2b)

a detailed view analogous to FIG. 2a a further embodiment of the flange connection arrangement;

FIG. 3a)

a first view of an embodiment of a flange, and

FIG. 3b)

a second view of the embodiment of the flange according to FIG. 3a ).

Fig. 1 1 shows a schematic longitudinal view of a flange connection assembly 1. Such a flange connection assembly 1 is used for releasably connecting a first, under bionic aspects optimized male flange 2 made of stainless steel and a second, conventional female flange 3 made of aluminum or an aluminum alloy. The first flange 2 is provided with a first bore 4 and with a projection embracing it, namely a pin 5 and has in a contact region 60 a surface minimized contact surface 6 with the second flange 3. The second flange 3 has a first bore 7 and a this encompassing and the pin 5 receiving recess 8. The first bore 4 of the male flange and the first bore 7 of the female flange put together a duct with an axis 9 fixed by a refrigerant, preferably R744 or a comparable refrigerant of an air conditioner, not shown a motor vehicle flows.

Deviating from the illustration according to FIG. 1 it is also possible in another embodiment, that the conduit within at least one of the flanges 2, 3 has a curved or angled course. For example, it is possible in that the duct has two duct sections which enclose an angle with each other, in particular an angle of 90 °. The first bores 4, 7 are then aligned locally there where they meet in the flange connection arrangement 1.

The duct goes on both sides in receiving bores 10 and 11 of larger diameter, which are soldered to ends 12a and 12b of a refrigerant pipe, welded or pressure-tight manner connected by another cohesive process. In this case, a first end 12b of a first refrigerant line is assigned to the first flange 2, wherein a second end 12a of a second refrigerant line is assigned to the second flange 3. Preferably, the first refrigerant pipe has the same material as the first flange 2, wherein preferably the second refrigerant pipe has the same material as the second flange 3. In this way, there is no problem of contact corrosion in the region of the transition between the flanges and their associated refrigerant pipes. A location where different materials meet is rather placed in the area of the flanges 2, 3, resulting in the advantages already described. At other points of a refrigerant circuit, in particular an air conditioning system of a motor vehicle, however, no pairing of different materials must be provided, so that particularly preferably a contact of different materials is given exclusively in the region of the two flanges 2, 3. This results in the already mentioned advantages.

In one embodiment, not shown, one or both mounting holes 10, 11 directly to a device, for example a heat exchanger, pressure-tight connected. Alternatively, it is possible that the male or female flange 2, 3 is part of a refrigeration component. As refrigeration component here is a component of a refrigerant or cooling circuit of a motor vehicle to understand, for example, an expansion valve, an evaporator, a condenser, a radiator, a compressor, a collector, a gas cooler or an internal heat exchanger.

Sealing surfaces 13a, 13b of the male flange 2 and the female flange 3 are sealed in a sealing region 40 by a soft, metallic sealing element 14, which is inserted between the two flanges.

In order to produce a pressure-tight connection between the male and female flange 2, 3, the Flanschverbindungsanungsanordnung 1 is provided with a clamping device. The first flange 2 has a second bore 16a, which is formed here as a through hole. The second flange 3 has a second bore 16b, which is formed here as a threaded bore. It is a clamping screw 17 is provided, which can be inserted through the through hole 16 a of the first flange 2 and screwed into the threaded bore 16 b of the second flange 3. In this way, the two flanges 2, 3 are clamped together. It is preferably provided that the clamping screw 17 is provided with a washer 15.

It can be seen that an axis 18 of the mutually aligned second bores 16a, 16b of the two flanges 2, 3 parallel to the axis 9 of the first holes 4, 7 and thus also of the duct extends, wherein it is arranged laterally offset from these. In this case, it is particularly preferably arranged centrally between the axis 9 and / or the sealing region 40 and the contact surface 6 in the contact region 60, particularly preferably in a center of gravity defined by these regions. In this way, a symmetrical introduction of clamping forces in the flanges 2, 3 by means of the clamping screw 17 is possible. An inner region 160 surrounding the second bore 16a of the first flange 2 is free of a contact surface, thus recessed, so that in any case the risk of contact corrosion between the flanges 2, 3 does not exist.

If the two flanges 2, 3 are urged against one another by means of the clamping screw 17, preferably symmetrical forces are introduced on the one hand into the sealing element 14 and on the other hand into the contact surface 6. The sealing element 14 is thereby deformed over preferably annularly formed sealing lips of the male flange 2 and the female flange 3 so that a gas-tight connection is formed.

In an embodiment not shown, the two flanges 2, 3 are braced by a union nut. The union nut is screwed by means of an internal thread on an external thread of one of the two flanges.

Due to the bionic geometry optimization of the first flange 2 and in particular by means of bionic geometry optimization introduced struts 19 in the loading direction, in spite of the minimized contact surface 6 and the bionic geometry optimization associated weight and space reduction an impermissible bending of the flange in particular in the region of the clamping force introduction, thus in the second bore 16 a surrounding inner region 160, not possible. Therefore, can be dispensed with material without disadvantages and a corresponding exemption can be realized here. This is all the more possible because the nobler material of the first flange 2 does not have to be kept as a sacrificial material.

It is understood that the illustrated embodiment is only a concrete realization of the flange connection arrangement 1 according to the invention. In particular, unlike the specific illustration, it is possible that the first flange 2 is designed as a female flange, wherein the second flange 3 is designed as a male flange. In particular, it is not absolutely necessary that the male flange has steel and is bionically optimized, but it is equally possible for the male flange to have aluminum and in this case preferably not be bionically optimized, wherein the female flange has steel and is bionically optimized is.

Fig. 2a ) shows a detailed view of the area minimized contact surface 6 according to Fig. 1 with a length L in the longitudinal direction of the first flange 2. The same and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description. A gap 20, which is established between the male and female flange 2, 3 after being pressed outside the contact region 60, namely outside the contact surface 6 and in particular in the inner region 160, has a height H which is dimensioned such that none Electrochemical contact corrosion can occur and any leaking medium during operation directly drained again and therefore can not function as an electrolyte for electrochemical contact corrosion. The areal minimized contact surface 6 is structurally arranged so that it has the largest possible, in particular a maximum distance to the pressure-carrying duct with the axis 9, so that at a local wall thickness reduction at the contact surface 6 by occurring electrochemical contact corrosion under no circumstances the pressure-bearing effect of the flange is impaired.

Fig. 2b ) shows a detailed view of a sealing arrangement of a further embodiment according to the present invention. Identical and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description. In this embodiment, an electrically insulating intermediate layer 22 was introduced between two opposing contact surfaces 6a and 6b of the flanges 2, 3, which may for example consist of an additional component - in particular of a plastic material - which may also be an electrically insulating coating which has been applied to one or both of the contact surfaces 6a, 6b. By introducing this intermediate layer 22, the occurrence of electrochemical contact corrosion can be avoided.

Fig. 3a ) shows an embodiment of a geometry under bionic aspects, space and weight optimized flange 2 in the male version with a contact surface 6, which here has two spaced by a recess 23 part contact surfaces 6c, 6d, and struts 19, 20 and 21, the extend in the direction of loading. The same and functionally identical elements are provided with the same reference numerals, so that insofar reference is made to the preceding description. Despite the minimized contact surface 6 and the weight and space optimization carried out an impermissible bending of the flange in the application is not possible, which ensures a gas-tight connection over the entire life.

Fig. 3a ) shows, moreover, a first view of the flange 2 obliquely from above. It is clear that the flange 2 here exactly two parallel plates, namely a first, upper plate 25 and a second, lower plate 27 has, which in the direction of in FIG. 1 illustrated axis 9 of the first bore 4 are spaced from each other. Between the plates 25, 27 web-like structural elements, namely here the struts 19, 20, 21 are provided, whose course is optimized in view of an expected load on the flange 2. This shows in particular that the material of the flange 2 is concentrated in higher-loaded areas or in areas of load paths, in particular at the location of the struts 18, 20, 21, wherein less loaded areas are recessed so that they in particular have no material.

The first bore 4 extends through the plates 25, 27. It also extends between the plates through a cylindrical first passage structure 29. Also, the second bore 16a extends through the plates 25, 27. Between the plates 25, 27 it extends through a substantially cylindrical second passage structure 31.

It can be seen that the second bore 16a is arranged here centrally with respect to the first bore 4 and the sealing region 40 on the one hand and the partial contact surfaces 6c, 6d and the contact region 60 on the other hand is. In particular, it preferably forms the center of gravity of a force triangle formed from the sealing surface 13a of the pin 5 and the partial contact surfaces 6c, 6d, whereby a particularly secure, stable and tight fastening of the flange 2 to another flange, in particular to the second flange 3, is possible.

On the side of the second bore 16a, two orientation bores 33a, 33b are arranged here, which serve to prevent confusion during assembly of the flange 2. In this case, a pin is preferably used in one of the two orientation bores 33a, 33b on a production line for the refrigerant line, which serves to prevent confusion and during assembly engages in a corresponding orientation bore of the second flange 3. Depending on the planned assembly, the pin is inserted either into the orientation bore 33a or into the orientation bore 33b. It is also possible that the flange 2 has only an eccentrically mounted orientation bore 33a, 33b. But this has the disadvantage that the flange 2 can then not be manufactured and provided as a common part. The in FIG. 3a ), however, can be manufactured as a common part, with its exact use with the insertion of the pin in exactly one of the two orientation holes 33a, 33b is set.

In the region of the recess 23, a dowel hole 35 is still arranged, which preferably continues in a third, substantially cylindrical, preferably cylindrical passage structure 37. In the dowel hole 35, a dowel pin is preferably used as intended, which serves the positionally relative arrangement of the flanges 2, 3, wherein it engages in a corresponding dowel hole of the second flange 3.

Fig. 3b ) shows a second view of the flange 2 according to FIG. 3a ) in an oblique view from below. Identical and functionally identical elements are provided with the same reference numerals, so that reference is made to the preceding description. Here again, the two plates 25, 27 can be seen, which are interconnected by the struts 19, 20, 21 and spaced from each other. In addition, the passage structures 29, 31, 37 are shown.

In summary, the geometry optimization of the stainless steel flange partner found by bionic considerations achieves significantly improved corrosion performance of a refrigerant pipe flanged joint in the aluminum / aluminum alloy on the one hand and stainless steel alloy on the other while minimizing weight and packaging space and providing competitive manufacturing costs can be.

1. 1. Flanschpaarung für Kältemittelleitungen, umfassend eine erste Bohrung und eine ein Dichtelement aufnehmende zweite Bohrung und einen Zapfen, wobei die beiden Flansche aus einer Materialpaarung aus Aluminium bzw. einer Aluminiumlegierung einerseits und einer rostfreien Stahllegierung anderseits bestehen und einen flächenmäßig minimierten Kontaktbereich aufweisen, deren Fläche zwischen 10 und 150 mm² groß ist; einen
2. 2. männlichen oder weiblichen Flansch aus einer rostfreien Stahllegierung nach Punkt 1, wobei in Belastungsrichtung aufgebrachte Verstrebungen einen minimalen Materialeinsatz bei gleichzeitig ausreichender Festigkeit und Dichtheit der Verbindung ermöglichen; eine
3. 3. Flanschpaarung nach einem oder mehreren der Punkte 1 und 2, wobei im Kontaktbereich zwischen dem männlichen und weiblichen Flansch eine elektrisch isolierende Zwischenlage eingebracht ist; eine
4. 4. Flanschpaarung nach einem oder mehreren der Punkte 1 bis 3, wobei im Kontaktbereich der männliche und/oder weibliche Flansch mit einer elektrisch isolierenden Beschichtung versehen ist; einen
5. 5. männlichen oder weiblichen Flansch aus einer rostfreien Stahllegierung nach einem oder mehreren der vorhergehenden Punkte 1 bis 4, wobei er durch ein Metallpulverspritzgussverfahren hergestellt wird; einen
6. 6. männlichen oder weiblichen Flansch aus einer rostfreien Stahllegierung nach einem oder mehreren der Punkte 1 bis 5, wobei er durch ein Feingussverfahren hergestellt wird; einen
7. 7. männlichen oder weiblichen Flansch aus einer rostfreien Stahllegierung nach einem oder mehreren der vorhergehenden Punkte 1 bis 6, wobei er durch ein additives Fertigungsverfahren hergestellt wird, und einen
8. 8. männlichen oder weiblichen Flansch aus einer rostfreien Stahllegierung nach einem oder mehreren der Punkte 1 bis 7, wobei er durch ein spanendes Fertigungsverfahren hergestellt wird.

After all, the invention relates to the following points:

1. 1. Flange pairing for refrigerant lines, comprising a first bore and a sealing element receiving the second bore and a pin, wherein the two flanges of a pair of aluminum or an aluminum alloy on the one hand and a stainless steel alloy on the other hand and have a minimized area contact area, the area between 10 and 150 mm ^{2 is} large; one
2. 2. male or female flange of a stainless steel alloy according to item 1, wherein applied in the loading direction Struts allow a minimal use of material while sufficient strength and tightness of the connection; a
3. 3. Flange pairing according to one or more of items 1 and 2, wherein in the contact region between the male and female flange, an electrically insulating intermediate layer is introduced; a
4. 4. Flange pairing according to one or more of the items 1 to 3, wherein in the contact region of the male and / or female flange is provided with an electrically insulating coating; one
5. 5. A male or female stainless steel alloy flange according to one or more of the foregoing 1 to 4, wherein it is produced by a metal powder injection molding method; one
6. 6. A stainless steel alloy male or female flange according to one or more of items 1 to 5, wherein it is manufactured by a precision casting process; one
7. A male or female stainless steel alloy flange according to one or more of the foregoing 1 to 6, wherein it is produced by an additive manufacturing method, and a
8. 8. A male or female stainless steel alloy flange according to one or more of items 1 to 7, wherein it is produced by a machining process.

Claims (16)

A flange connection assembly for a refrigerant pipe having a first flange and a second flange, the first flange having a first material, the second flange having a second material, wherein the first material and the second material are different from each other, and wherein the first material and differentiate the second material in particular in their electrochemical potential in such a way that they form an electrochemical local element with one another. Flange connection arrangement according to claim 1, characterized in that the first flange steel, in particular stainless steel, in particular stainless steel, preferably ferritic steel, martensitic steel or austenitic steel, in particular austenitic stainless steel, having, wherein the first flange is preferably made of one of said materials, and / or that the second flange comprises a light metal or a light metal alloy, in particular aluminum or an aluminum alloy, wherein it preferably consists of one of said materials. Flange connection arrangement according to one of the preceding claims, characterized in that the first flange and the second flange abut each other in a contact region, wherein the contact region a minimally loaded surface area, in particular of at least 10 mm ² to at most 150 mm ² , preferably of at least 25 mm ² to at most 100 mm ² , preferably from at least 35 mm ² to at most 75 mm ² , more preferably of 50 mm ² , having. Flange connection arrangement according to one of the preceding claims, characterized in that the second flange has a first bore for passage of refrigerant, which is aligned with a first bore of the first flange for the passage of refrigerant, wherein the second flange preferably a second bore, in particular a through hole or a threaded bore for receiving a fastening means, preferably a screw, which is aligned with a second bore of the first flange, in particular a through hole or a threaded bore, for receiving a fastening means, preferably a screw. Flange connection arrangement according to one of the preceding claims, characterized in that the first flange has a first bore engaging around the projection or a first hole encompassing recess, in particular a first bore encompassing the annular groove, said second flange having a first bore encompassing recess, in particular an annular groove, or a protrusion embracing the first bore, wherein the protrusion of the first flange engages in the recess of the second flange, or wherein the protrusion of the second flange engages in the recess of the first flange. Flange connection arrangement according to one of the preceding claims, characterized in that in the recess, which surrounds the first bore of the first or the second flange, a sealing element is arranged. Flange connection arrangement according to one of the preceding claims, characterized in that between the first flange and the second flange in the contact region an electrically insulating intermediate layer is arranged, wherein preferably at least one of the flanges on a contact surface to the other flange an electrically insulating layer, in particular an electrically insulating coating, comprising. Flange for a connection point in a refrigerant line, in particular for a Flanschverbindungsanordnung according to one of claims 1 to 7, having a first bore for passage of a refrigerant, characterized in that on the flange a contact surface for engagement with another flange of a Flanschverbindungsanordnung is formed the contact surface has a minimized weight, in particular at least 10 mm ² to at most 150 mm ² , preferably at least 25 mm ² to at most 100 mm ² , preferably at least 35 mm ² to at most 75 mm ² , more preferably 50 mm ² , having. Flange according to claim 8, characterized in that the flange has a lightweight structure, in particular a bionic structure, preferably a profiled structure or a truss structure. Flange according to one of claims 8 and 9, characterized in that the material of the flange is concentrated in higher loaded areas or in areas of load paths, wherein preferably at least a small loaded area is recessed, in particular no material, and / or that the flange at least having a strut extending in a loading direction. Flange according to one of the preceding claims 8 to 10, characterized in that the flange has at least two, preferably exactly two substantially parallel, preferably parallel plates which are spaced apart by web-like structural elements, in particular webs, and interconnected, wherein the first Preferably bore extends through the plates and between the plates by a substantially cylindrical, preferably cylindrical first passage structure. Flange according to one of the preceding claims 8 to 11, characterized in that the flange has a second bore, in particular a through bore or a threaded bore for receiving a fastener, preferably a screw, wherein the second hole preferably through the plates of the flange and extends between the plates through a substantially cylindrical, preferably cylindrical second passage structure. Flange according to one of the preceding claims 8 to 12, characterized in that the second bore is arranged centrally on the flange, wherein the contact region - preferably symmetrically, particularly preferably viewed from the second bore symmetrical to the first bore or to a projection or a Recess which / which surrounds the first bore -is disposed in an outer region of the flange, wherein an inner region of the flange surrounding the second bore is free of a contact surface. Flange according to one of the preceding claims 8 to 13, characterized in that the contact surface with an electrically insulating layer, preferably an electrically insulating coating, is provided. Flange according to one of the preceding claims 8 to 14, characterized in that the flange is made in a process selected from a group consisting of a generative manufacturing process, an additive manufacturing process, a metal powder injection molding process, a precision casting process, a forging process and a machining process. Flange connection arrangement according to one of claims 1 to 7, characterized in that the first flange is designed as a flange according to one of claims 8 to 15.

Images